A novel high efficiency high power density three-port converter based on interleaved half-bridge converter for renewable energy applications

Multiport dc/dc converters are widely employed in renewable energy generation systems to provide stable power to key loads. A novel three-port converter topology that interfaces one source port, one bidirectional storage port, and one isolated load port is proposed based on a modified version of two interleaved half-bridge converters. An interleaved bidirectional buck-boost converter parasitized on the primary side circuit is used to interface the renewable source with the battery. A novel three-level full-bridge converter, interfacing the load with the renewable source, is built by parallel connecting the two half-bridge converter and sharing a common output filter. Soft-switching operation and single stage power conversion between any two of the three ports are achieved with the proposed converter. Three voltage-levels are generated and applied to the output filter inductor. Thus, the size and volume of the output filter is reduced greatly. As a result, high efficiency and high power density is achieved. The operation principles, modulation schemes and power management strategies of the proposed converter are presented and analyzed in detail, and verified with experimental results.